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Quantum Coherence Found Fueling Photosynthesis
Gaygirlie writes "Ars Technica has posted an interesting article about new findings regarding quantum physics and photosynthesis. Their excerpt for the article: 'Physicists have found the strongest evidence yet of quantum effects fueling photosynthesis. Multiple experiments in recent years have suggested as much, but it has been hard to be sure. Quantum effects were clearly present in the light-harvesting antenna proteins of plant cells, but their precise role in processing incoming photons remained unclear.' Here's a little background info for those unaware of what coherence and quantum coherence are."
helped me, yet again, realize how little I understand quantum physics.
If quantum effects are real (as they demonstrably are), should it be a surprise that evolution made use of them?
http://xkcd.com/865
Space Nutters keep telling me we need to get off this mud ball and explore the total vacuum of space, since there's nothing left to explore on this rock.
But it sounds to me like that's a relic of the 1960s Space Age and is outdated thinking. We are in the Information Age now, and we are starting to get a real good grasp of how matter operates in the "life" mode. Life extension is the future, by understanding the unbelievable complexity of life, not the very simple fact of empty space.
This *might* be related to my wife's PhD research from several years back. Proton Coupled Electron Transfer. She's in a seminar right now, but when she's back at her desk, I'll past this by her to see if it relates. I could be totally wrong, but I know physicists approach the same kinds of things using different terms and models than chemists. Either way, PCET is an interesting effect that also happens in photosynthesis:
https://en.wikipedia.org/wiki/PCET
"$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien
Up yours!
"hard to be sure"
Ha! Who would have guessed - uncertainty in quantum mechanics!
The U.K. has the world's largest civilian stockpile of plutonium.
A civilian stockpile? Can someone explain to me how the UK has a civilian stockpile of plutonium?
I've seen some comments stating that 'meh photoelectric effect nothing new to see here'. While it is true that emission/absorption is subject to quantum mechanics, specifically the photo-electric effect being governed by the work function hf = phi - eV, with hf = hc/lambda, phi being the work-function of the material, and eV being the 'escape velocity' of the electrons; the point being that energy emitted/absorbed must satisfy the above relationship, otherwise the photo-electric effect does not work.
What I believe this study is saying is that 'antennae' structures can act as a single quantum mechanical unit (the coherence) so that the incoming insolar radiation has more paths for electron conduction, since the transfer of energy/conduction of electrons is limited to the quantization by the work function, i.e., charge quantization limits the specific wavelengths/frequencies/energies of incoming photons that the plant can use to harvest energy, so in effect the evolution of these 'antennae' structures over time allows for a coherent systems that can act as single particles, with the different permutations of antennas allowing for vastly more permutations of allowed incoming wavelengths to satisfy the Schrodinger eqn (probably not dirac since these are most likely not relativistic interactions, at least the effects are negligible).
I deal more with relativity and QED/QCD, but that's my interpretation of the article.
'We are trying to prove ourselves wrong as quickly as possible, because only in that way can we find progress.' RPF
The plants REALLY do have a chance against the Zombies. They can use their quantum energy blasters!!!!
This is something we tested by accident with our zero-light fodder system. We found a different pathway to stimulate, however, and do it via pulsing current through the nutrient solution at insanely high frequencies, using induction coils. Keeps the fodder grass nice and green.
This study will help us understand why this works.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
Any evolved system will use all possible inputs to its fitness function, simply because there isn't any mechanism of focusing. Unlike human design, which is all about making known mechanisms work and all but those mechanism are ignored, and even actively avoided. When early researchers used solid-state electronics to make genetic algorithms, often the "solution" only worked on the specific hardware circuit it was learnt on (not supposedly identical copies), because it relied on otherwise-undefined race conditions in the silicon.
So don't be surprised if quantum effects are also used by your brain cells ... and by your anal sphincter.
what kinda efficiency we talking here?
If you think our technology has traveled a long way so far, consider still how far ahead evolution is. Things like this amaze me.
spooky action at a distance " (at the heart of quantum coherence) had never been further than his salad bowl...
MSBPodcast.com The opinions expressed here are my own. If you don't like 'em... Think up your own stuff.
The way people often describe quantum decoherence is that an "observation" occurs that "collapses the wave function" and causes a superposition to converge to a single classical state. But I really think that's a misleading explanation. For one thing, surely the same phenomena occurred long before there were any intelligent observers, and secondly, scientists have observed things in states of quantum superposition WITHOUT causing decoherence.
The way think of it (as a total amateur in the area) is that rather than the wave function representing probabilities of states, it represents the degrees to which something is in all of those states. An "observation" is just like many other interactions with the environment that change those probabilities (or degrees of state).
Then there's the question of why subatomic particles (and some larger things) can be in states of quantum superposition, while larger things cannot. Penrose had a suggestion here. It's gravity. The more massive you are, the less your superimposed states can diverge from one another. Even a planet is in a state of superposition, but all of those states overlap so much relative to the dimensions of the object that you cannot distinguish them.
This highly mathematical discussion of photosynthesis is completely unnecessary. One need only understand what a dipole is, that water is an incredible dipole, and the capabilities of gels, in order to understand how it is that proteins structure the water. And from there, it is a short logical leap to understand how life extracts energy from electricity. Gerald Pollack presents all of this in terms of the very clearly-stated underlying physics of phase transitions in gels (and polymers) within his book "Gels, Cells and the Engines of Life". Mae Wan Ho also has much to say on this topic, adding that proton-jumping is possible (aka semiconduction in condensed matter physics) in this structured water.
Put simply: Proteins are covered in alternating charges designed specifically to accept water. Since water is such a strong dipole, it locks onto the protein in such a manner that a 3d lattice of alternating spins is achieved. This "structured water" behaves COMPLETELY DIFFERENTLY from unstructured water. This is an example of a phase transition in a gel. The body can structure and unstructure this water at will. And that simple capability can be used to actually explain every single one of the cell's functionalities.
Gerald Pollack's investigation into the mistakes in cell biology are revolutionary, and these findings will herald a major medical revolution once they become more widely known and studied. Slashdotters will be very interested in the quantum computing implications, as it all suggests quite directly that we can create custom "living" quantum computers -- life whose sole purpose is to behave as a computer. One need only fully understand all of the various biopolymers phase transitions, and piece them together into a functional system. In fact, this is exactly what happened "accidentally", when life formed.
Back in '07, this article was published...
http://www.physics.gla.ac.uk/~dtngo/Article/Nature_446_782_2007.pdf
As I understand this, in the classical photosynthesis model, energy transfer is sort of modeled like the incoming sunlight excites a population of light absorbing "antennea" pigments which transfer the energy to reaction centers where long term energy storage is initiated (e.g., the CO2->sugar conversion). If the energy transfer was "classically" photoelectric, you'd see a system where light excites a population of antenna of different pigments, which then re-emit the energy at a wavelength compatible with the photosynthesis.
If this was true, you could potentially measure electric field and look for frequency of absorbtion and re-emission (they would look like 2 frequency peaks). However, if there were some sort of state coupling, you'd also see beat frequencies corresponding to the difference in energies between various pigments and the re-emission. That in itself is not that interesting, but the fact that when they sent in pulses, these frequencies corresponding to beat frequencies seems to persist longer than the expected coherence time which apparently suggests that coherence lasts long enough to transit all the way from the antenna/pigments to the location of energy conversion (in this case 660 femtoseconds).
The next step is to hypothesize that you can use QM and treat the full system as essentially coherently absorbing light at with the exactly correct antenna/pigment and re-emitting it essentially lossless to the conversion point, rather than it absorbing a collection/population of antenna over a period of time (some of them efficiently, some of them less efficienty), and re-emitting the energy (the classical model). Of course this is a pretty big step and is not a constructive argument, but it is in line with observations about photosynthetic efficiency and there is now more measurements to back up the potential (QM/coherence) pathway which might be able to explain that efficiency..
Oh look, a 43 year old Anonymous Coward with delusions of living somewhere other than mom's basement. Get an education, social skills, a job, a girlfriend (need I go on?), you fool.
A common misstatement. Planck's constant is a quantum of action, not energy. It has the dimensions of angular momentum, which is momentum*distance or energy*time, i.e. a volume of phase space (4-space in special relativity, dot product of position and momentum 4 vectors). Two free charged particles can exchange arbitrarily small amounts of energy over a long period of time, classical electrodynamics describing that perfectly. However a bound particle can only exchange discrete amounts of energy, the smallest corresponding to a Planck's constant change in action.
To say that "a photon" of a given energy is involved in the interaction between two bound states is a leap of faith. Photons emerge from the Bose-Einstein statistics of spin 1 particles, and are created and destroyed using the statistical raising and lowering operators that describe the energy change in the electromagnetic field.
You're quite right. I think the best route to having off-Earth colonies is to engineer people so that they can deal with zero-G, high radiation, low temperatures, and live off sunlight.
It's not us, but our solid-state descendants who will inherit the galaxy.
--PM
Orch-OR theory (Quantum Mind theory)?
If plants are doing it, I would be really surprised if such a nifty trick wouldn't also be used in communication between neurons in the brain.
http://en.wikipedia.org/wiki/Orch-OR
The main objection (in the face of mounting evidence and backing theory) is that quantum coherence could never be maintained at biological temperatures/environments... well I guess that's not really an issue any more.
I can't wait to see what else the emerging field of quantum biology is going to bring :D
Isn't it near madness to continue to assert that these kinds of systems evolved naturalistically via Darwinian mechanisms? While there may be some other mechanism of evolution at work (see Shapiro, for example), the idea that random mutation and natural selection could produce this kind of complexity is laughable. Its a valid hypothesis, and its OK to say this *may* have evolved Darwinistically, but there's no evidence that anything nontrivial could be built this way.
Darwin knew nothing of what goes on at the molecular level, and he distorted the scientific method in a way that biology has yet to recover from.